Methods

Overall study design

The EDSMAR study began in February 2016 with a feasibility study (pilot phase), which was completed in January 2017. The pilot phase included 50 case patients with breast cancer (25 in Rabat and 25 in Fez) and 50 matched control subjects without breast cancer (25 in Rabat and 25 in Fez). The project is now being expanded to a larger case–control study including 500 breast cancer cases (250 in Rabat and 250 in Fez) and 500 matched controls (250 in Rabat and 250 in Fez).

Women diagnosed with breast cancer at the National Institute of Oncology’s Sheikha Fatma Centre for Gynaecological-Mammary Oncology in Rabat or the Cancer Research Institute of the Centre Hospitalier Universitaire (CHU) Hassan II in Fez are invited to participate in the study immediately after their diagnosis, before any treatment has begun. To better understand why these women developed breast cancer, investigators also invite other women, who have not developed the disease, to participate in the study as controls. Each case patient is individually matched with a control subject who lives in the same neighbourhood and is approximately the same age (± 5 years).

The women recruited to the study are asked to complete questionnaires on lifestyle, diet, and environmental factors, and to provide anthropometric measurements as well as blood and urine specimens to be used for research purposes. Tumour samples are also collected, to identify molecular breast cancer subtypes by immunohistochemical analyses. Various types of adiposity are measured using dual-energy X-ray absorptiometry (DXA).